(i) Resonance light scattering is an esoteric technique, which takes advantage of the complex behavior of the refractive index within the absorbance bands of high molecular aggregates of some chromophores. Recently numerous biochemical assays have been published, which claim to use this methodology. We have shown that most of the scattering peaks detected in these experiments are spurious, arising from the properties of the intrument's photomultiplier, not from the molecular species under study. A simple method for the detection of this artifact has been descibed. (McPhie P. 2006) (ii) Antibody presentation is a key step in the initiation of the adaptive immune response, depending on the expression of costimulatory molecules. Immune-enhancing oligodeoxynucleotides (ODNs)increase the expression of these molecules. CD measurements were used to show that several of these regulatory ODNs contain guanine(G)-tetrad structures. Heat treatment of these ODNs which diminishes their regulatory properties also destroyed the G-tetrads. ((Wang J. et al 2007) (iii) Optical studies on the structures of amyloid peptides and proteins are continuing.